How to Send SMS in Paraguay: 2025 Compliance Guide & API Integration

Paraguay SMS Market Overview

Market Conditions: Paraguay has a growing mobile market with high SMS adoption rates and mobile penetration exceeding 95%. Three major operators dominate the country's mobile landscape: Tigo (51 – 55% market share), Personal Paraguay (second-largest operator, owned by Telecom Argentina subsidiary Núcleo S.A.), and Claro Paraguay (11 – 26% market share, owned by América Móvil). The Paraguay Telecom Mobile Network Operator (MNO) Market is expected to reach USD 699 million in 2025. While OTT (Over-The-Top) messaging apps like WhatsApp are popular (offered free with data bundles), SMS remains a crucial channel for business communications and notifications due to its reliability and universal reach. Android devices hold a significant market share advantage over iOS in the region.

Sending SMS in Paraguay: Supported Features and Technical Capabilities

Paraguay supports basic SMS functionality with some limitations on advanced features. Focus your strategies on one-way messaging for business communications.

Two-Way SMS Support in Paraguay

Major SMS providers do not support two-way SMS in Paraguay. Design your messaging strategies around one-way communications only.

Workarounds for Interactive Communications:

• Include unique URLs with tracking parameters for responses
• Add QR codes linking to web forms
• Direct recipients to WhatsApp Business (offered free with data bundles)
• Use webhook callbacks for delivery receipt tracking

Concatenated Messages (Segmented SMS)

Support: Yes. Availability may vary by sender ID type.

Message Length Rules:

• GSM-7 encoding: 160 characters per segment
• Unicode (UCS-2): 70 characters per segment
• Concatenated GSM-7: 153 characters per segment (7 chars for header)
• Concatenated Unicode: 67 characters per segment (3 chars for header)

Cost Impact Example:

• 150-character message = 1 SMS unit
• 161-character message = 2 SMS units
• 300-character message = 2 SMS units
• 301-character message = 3 SMS units

MMS Support in Paraguay

Paraguay does not directly support MMS messages. Providers automatically convert MMS to SMS with an embedded URL link where recipients view the multimedia content.

URL Hosting Requirements:

• Providers host media files on their CDN infrastructure
• Links typically expire after 30 – 90 days (provider-dependent)
• Recipients need mobile data or Wi-Fi to view content
• Image optimization recommended (< 500 KB for best performance)

Provider Support:

• Twilio: Converts MMS to SMS + URL automatically
• Sinch: Supports MMS-to-SMS conversion
• MessageBird: Check account settings for MMS conversion availability
• Plivo: Converts MMS with URL shortlink

Recipient Phone Number Compatibility

Number Portability

Mobile Number Portability (MNP) has been operational in Paraguay since November 30, 2012. Informática El Corte Inglés S.A., selected by telecom operators, administers the MNP system. Customers can port their numbers for free, with the activation process taking 24 hours and the actual transfer occurring within 2 hours (between 1:00 – 5:00 AM). Any person or company with active lines (prepaid, postpaid, or corporate) can port their number. During 2019, Paraguay recorded 838,988 numbers ported, demonstrating strong user adoption.

Paraguay Phone Number Format:

• Country code: +595
• Total digits: 9 (after country code)
• Mobile format: Mobile numbers begin with "9" (e.g., +595 9XX XXX XXX)
• Landline format: First 2 – 3 digits are area code (e.g., 20, 30, 40), remaining 6 – 7 digits are subscriber number
• E.164 format: +595 XXXXXXXXX (no leading "0" for international calls)
• Domestic format: Use national prefix "0" before area/mobile code for domestic long distance

Sending SMS to Landlines

You cannot send SMS to landline numbers in Paraguay. Landline attempts result in delivery failures with API error 400 (code 21614). Failed messages do not appear in logs and do not incur charges.

Prevent Landline Attempts:

// Example: Paraguay mobile number validation
function isParaguayMobile(phoneNumber: string): boolean {
  const mobilePattern = /^\+5959[0-9]{8}$/;
  return mobilePattern.test(phoneNumber);
}

Paraguay SMS Compliance: Law 6534/2020 and CONATEL Regulations

Law No. 6534/2020 (Personal Credit Data Protection Law) governs SMS communications involving credit-related personal data. The National Telecommunications Commission (CONATEL) oversees telecommunications services and enforces messaging regulations. Law 6534/2020 established two enforcement authorities: the Central Bank of Paraguay (BCP) and the Secretariat for the Defense of the Consumer and the User (SEDECO).

Important Note: Paraguay does not have a National Data Protection Authority. Law 6534/2020 regulates credit information systems in banking and financial entities, not general SMS marketing practices.

For Non-Credit SMS Marketing:

• Follow general consumer protection laws under SEDECO
• Obtain explicit consent before sending commercial messages
• Honor all opt-out requests immediately
• Maintain suppression lists and consent documentation
• Consult local legal counsel for industry-specific requirements

Consent and Opt-In

Explicit Consent Requirements:

• Obtain written or electronic consent before sending marketing messages
• Maintain consent records for at least 2 years
• Clearly state the purpose of messaging during opt-in
• Provide consent language in both Spanish and Guaraní

Best Practices for Documentation:

• Maintain detailed records of consent acquisition method and timestamp
• Store opt-in source (web form, SMS keyword, etc.)
• Keep proof of consent messaging and terms presented to users

Language Context: According to Paraguay's 2024 National Institute of Statistics survey, 38.7% of the population aged five or older speaks both Guaraní and Spanish at home, 30% communicate mainly in Guaraní, and 28.5% in Spanish. Bilingual SMS capabilities enhance reach, particularly in rural areas.

Example Bilingual SMS Templates:

Spanish: "Su pedido #12345 está listo para recoger. Reply STOP to unsubscribe."
Guaraní: "Ne ñe'ẽ #12345 oĩma ojegueraha hag̃ua. Emoñe'ẽ AÑICHÉMA ani hag̃ua."

Spanish: "Confirme su cita para el 15/03 a las 10:00. Reply CONFIRMAR."
Guaraní: "Emoañete ne jeikombo 15/03-pe 10:00-pe. Emoñe'ẽ CONFIRMAR."

HELP/STOP and Other Commands

• Support standard opt-out keywords in all SMS campaigns:
  • STOP, PARAR, BASTA (Spanish)
  • AÑICHÉMA (Guaraní)
• Provide clear service information in HELP/AYUDA messages
• Send response messages in the same language as the user's request
• Send opt-out confirmation within 24 hours

Do Not Call / Do Not Disturb Registries

Paraguay does not maintain an official Do Not Call registry. However, you should:

• Maintain your own suppression lists
• Honor opt-out requests immediately
• Remove opted-out numbers within 24 hours
• Regularly clean contact lists to remove inactive numbers

Time Zone Sensitivity

Paraguay Time (PYT) was permanently set to UTC-3 year-round as of 2024. Paraguay eliminated seasonal Daylight Saving Time (DST) changes, which had been observed since 1975.

• Timezone: Paraguay Time (PYT), UTC-3 (permanent, no DST)
• Recommended Sending Hours: 8:00 AM – 8:00 PM local time (PYT/UTC-3)
• Urgent Messages: Send outside these hours only for critical notifications
• Holiday Considerations: Avoid sending on Paraguay's 14 national holidays unless essential. Key holidays include Heroes' Day (March 1), Holy Week (Semana Santa with Holy Thursday and Friday as public holidays), Workers' Day (May 1), and Independence Day

Recent CONATEL Updates (2024 – 2025):

• Resolución Directorio N° 1752/2024: Allocated 3300 – 3700 MHz frequency band for mobile services
• Resolución Directorio No. 1035/2025 (April 23, 2025): Authorized 5,925 – 6,425 MHz band for low-power wireless access systems (Wi-Fi 6E)

Paraguay SMS Sender ID Options: Alphanumeric, Long Codes & Short Codes

Alphanumeric Sender ID

Operator network capability: Not supported Registration requirements: N/A Sender ID preservation: Carriers overwrite all alphanumeric IDs with random shortcodes or local long codes

What Recipients See:

• Random 5-6 digit shortcode (most common)
• Shared pool number that varies per message
• No consistent brand identification via sender ID

Brand Registration Alternatives:

• Include your brand name in the first line of message body
• Use consistent signature: "– YourCompany"
• Apply for dedicated short code (8 – 12 weeks provisioning)
• Register trademark with DINAPI for brand protection

Long Codes

Domestic vs. International:

• Domestic long codes not supported
• International long codes supported but with limitations

Sender ID preservation: No, carriers do not preserve original sender ID Provisioning time: Immediate for international long codes Use cases: Transactional messages, alerts, and notifications

Short Codes

Support: Available through local carriers Provisioning time: 8 – 12 weeks for approval Use cases:

• High-volume marketing campaigns
• Two-factor authentication
• Customer service communications

Paraguay SMS Content Restrictions and Prohibited Industries

Prohibited Content:

• Gambling and betting services
• Adult content or explicit material
• Unauthorized financial services
• Political campaign messages without proper authorization
• Religious content without explicit consent

Regulated Industries:

• Financial services require CONATEL approval
• Healthcare messages must comply with privacy regulations
• Educational institutions need proper accreditation

Content Filtering

Carrier Filtering Rules:

• Carriers scrutinize URLs for malicious content
• Providers block keywords related to restricted industries
• Filters may catch multiple exclamation marks or all-caps messages

Best Practices to Avoid Blocking:

• Avoid URL shorteners
• Use clear, professional language
• Limit special characters and symbols
• Include your company name in message body

SMS Best Practices for Paraguay: Messaging Strategy & Optimization

Messaging Strategy

• Keep messages under 160 characters when possible
• Include clear call-to-action
• Use personalization tokens (customer name, account info)
• Maintain consistent sender identity

Sending Frequency and Timing

• Limit to 4 – 5 messages per month per recipient
• Respect local holidays and cultural events
• Avoid sending during siesta hours (1:00 PM – 3:00 PM)
• Space out campaign messages to prevent fatigue

Localization

• Primary languages: Spanish and Guaraní
• Consider bilingual messages for wider reach
• Use local date/time formats (DD/MM/YYYY)
• Adapt content for local cultural context

Opt-Out Management

• Process opt-outs within 24 hours
• Maintain centralized opt-out database
• Confirm opt-out status via SMS
• Conduct regular audits of opt-out list compliance

Testing and Monitoring

Testing Checklist:

• ☐ Test across major carriers (Tigo, Personal, Claro)
• ☐ Verify E.164 number formatting
• ☐ Test concatenated message splitting
• ☐ Validate opt-out keyword responses
• ☐ Check special character rendering (Spanish/Guaraní)
• ☐ Test timezone-aware scheduling

Key Metrics to Track:

Monitoring Tool Recommendations:

• Twilio Console: Real-time delivery logs and error tracking
• Grafana + Prometheus: Custom dashboards for multi-provider monitoring
• Datadog: APM and alerting for SMS service health
• PagerDuty: Alert routing for delivery failures

Paraguay SMS API Integration: Twilio, Sinch, MessageBird & Plivo

Twilio

Twilio provides a robust SMS API with comprehensive support for Paraguay. Integration requires account credentials and proper phone number formatting.

Key Parameters:

• Account SID and Auth Token for authentication
• From number must be a valid Twilio number
• Recipient numbers in E.164 format (+595XXXXXXXXX)

import { Twilio } from 'twilio';

// Initialize Twilio client with credentials
const client = new Twilio(
  process.env.TWILIO_ACCOUNT_SID,
  process.env.TWILIO_AUTH_TOKEN
);

async function sendSMSToParaguay(
  to: string,
  message: string
): Promise<void> {
  try {
    // Validate Paraguay phone number format
    if (!to.startsWith('+595')) {
      throw new Error('Invalid Paraguay phone number format');
    }

    const response = await client.messages.create({
      body: message,
      to: to,  // Example: +595981234567
      from: process.env.TWILIO_PHONE_NUMBER,
    });

    console.log(`Message sent successfully! SID: ${response.sid}`);
  } catch (error) {
    console.error('Error sending message:', error);
    throw error;
  }
}

Sinch

Sinch offers direct carrier connections in Paraguay with support for high-volume messaging.

Key Parameters:

• Service Plan ID and API Token
• Sender ID (carriers will overwrite with local format)
• Destination number in international format

import axios from 'axios';

interface SinchSMSResponse {
  id: string;
  status: string;
}

async function sendSinchSMS(
  to: string,
  message: string
): Promise<SinchSMSResponse> {
  const SINCH_BASE_URL = 'https://sms.api.sinch.com/xms/v1';
  const SERVICE_PLAN_ID = process.env.SINCH_SERVICE_PLAN_ID;

  try {
    const response = await axios.post(
      `${SINCH_BASE_URL}/${SERVICE_PLAN_ID}/batches`,
      {
        from: process.env.SINCH_SENDER_ID,
        to: [to],
        body: message,
      },
      {
        headers: {
          'Content-Type': 'application/json',
          Authorization: `Bearer ${process.env.SINCH_API_TOKEN}`,
        },
      }
    );

    return response.data;
  } catch (error) {
    console.error('Sinch SMS Error:', error);
    throw error;
  }
}

MessageBird

MessageBird provides reliable SMS delivery in Paraguay through their REST API.

import { MessageBird } from 'messagebird';

class MessageBirdService {
  private client: MessageBird;

  constructor(apiKey: string) {
    this.client = new MessageBird(apiKey);
  }

  async sendSMS(
    to: string,
    message: string
  ): Promise<any> {
    const params = {
      originator: 'YourBrand',
      recipients: [to],
      body: message,
      datacoding: 'auto', // Handles special characters
    };

    return new Promise((resolve, reject) => {
      this.client.messages.create(params, (err, response) => {
        if (err) {
          reject(err);
        } else {
          resolve(response);
        }
      });
    });
  }
}

Plivo

Plivo offers SMS capabilities in Paraguay with support for Unicode messages.

import * as plivo from 'plivo';

class PlivoService {
  private client: plivo.Client;

  constructor() {
    this.client = new plivo.Client(
      process.env.PLIVO_AUTH_ID,
      process.env.PLIVO_AUTH_TOKEN
    );
  }

  async sendSMS(
    to: string,
    message: string
  ): Promise<any> {
    try {
      const response = await this.client.messages.create({
        src: process.env.PLIVO_SOURCE_NUMBER,
        dst: to,
        text: message,
        url_strip_query_params: false
      });
      return response;
    } catch (error) {
      console.error('Plivo SMS Error:', error);
      throw error;
    }
  }
}

API Rate Limits and Throughput

Provider-Specific Rate Limits:

Throughput Optimization:

• Use batch processing for volumes > 1,000/hour
• Implement queue systems for high-volume campaigns
• Apply exponential backoff for retry logic

Exponential Backoff Implementation:

async function sendWithRetry(
  sendFn: () => Promise<any>,
  maxRetries: number = 3
): Promise<any> {
  for (let attempt = 0; attempt < maxRetries; attempt++) {
    try {
      return await sendFn();
    } catch (error: any) {
      // Check if error is rate limit (429) or network issue
      if (error.status === 429 || error.code === 'ETIMEDOUT') {
        const delay = Math.pow(2, attempt) * 1000; // 1s, 2s, 4s
        console.log(`Retry ${attempt + 1}/${maxRetries} after ${delay}ms`);
        await new Promise(resolve => setTimeout(resolve, delay));
      } else {
        throw error; // Non-retryable error
      }
    }
  }
  throw new Error('Max retries exceeded');
}

Throughput Management Strategies:

• Implement queue for high-volume sending
• Create message prioritization system
• Apply automatic rate limiting and throttling
• Use batch processing with optimal chunk sizes

Error Handling and Reporting

Logging Best Practices:

• Implement structured logging with correlation IDs
• Track delivery receipts (DLRs)
• Monitor carrier responses
• Set up alerting for error thresholds

DLR Webhook Handling:

import express from 'express';

const app = express();

app.post('/webhook/delivery-receipt', express.json(), (req, res) => {
  const { MessageSid, MessageStatus, To, ErrorCode } = req.body;

  console.log(`DLR for ${MessageSid}: ${MessageStatus}`);

  if (MessageStatus === 'failed' || MessageStatus === 'undelivered') {
    console.error(`Delivery failed to ${To}. Error: ${ErrorCode}`);
    // Trigger alert or retry logic
  }

  res.status(200).send('OK');
});

Common Error Scenarios:

• Invalid phone numbers
• Network timeouts
• Carrier rejections
• Rate limit exceeded

Recap and Additional Resources

Key Takeaways:

1. Format all numbers in E.164 format (+595XXXXXXXXX)
2. Implement proper error handling and retry logic
3. Monitor delivery rates and carrier responses
4. Follow local compliance requirements
5. Maintain opt-out lists and honor unsubscribe requests

Next Steps:

1. Review CONATEL regulations at www.conatel.gov.py
2. Review Law No. 6534/2020 (Personal Credit Data Protection Law) for credit-related data handling
3. Consult with local legal counsel for compliance verification, noting the absence of a National Data Protection Authority
4. Set up monitoring and reporting systems
5. Test thoroughly across all major carriers (Tigo, Personal, Claro)

Additional Resources:

• CONATEL Official Website
• Paraguay Data Protection Law (Law 6534/2020)
• Central Bank of Paraguay (BCP)
• SEDECO (Consumer Protection Authority)
• SMS Compliance Best Practices Guide
• E.164 Phone Number Format Explained
• SMS API Rate Limiting Strategies
• Technical support contacts for major carriers:
  • Tigo: support@tigo.com.py
  • Personal: soporte@personal.com.py
  • Claro: ayuda@claro.com.py

Frequently Asked Questions (FAQ)

Does Paraguay support mobile number portability (MNP) for SMS?

Yes. Mobile Number Portability has been operational in Paraguay since November 30, 2012. Informática El Corte Inglés S.A. administers the service, and it is completely free for customers. The activation process takes 24 hours, with the actual transfer occurring within 2 hours (between 1:00 – 5:00 AM). Any person or company with active lines (prepaid, postpaid, or corporate) can port their number. During 2019, Paraguay recorded 838,988 numbers ported.

What phone number format do I need for sending SMS to Paraguay?

Use the E.164 international format: +595 followed by 9 digits. Mobile numbers begin with "9" (e.g., +595 9XX XXX XXX). For domestic long distance calls within Paraguay, use the national prefix "0" before the area or mobile code. Do not include the leading "0" when formatting numbers for international SMS delivery.

What are the SMS compliance requirements in Paraguay?

Comply with Law No. 6534/2020 (Personal Credit Data Protection Law), though its scope is limited to credit-related personal data. CONATEL oversees telecommunications compliance. Obtain written or electronic consent before sending marketing messages, maintain consent records for at least 2 years, and support opt-out keywords in both Spanish (STOP, PARAR, BASTA) and Guaraní (AÑICHÉMA). Send opt-out confirmation within 24 hours. Note that Paraguay does not have a National Data Protection Authority.

Which mobile operators support SMS in Paraguay?

Paraguay has three major operators: Tigo (51 – 55% market share, the dominant operator), Personal Paraguay (second-largest operator, owned by Telecom Argentina subsidiary), and Claro Paraguay (11 – 26% market share, owned by América Móvil). Mobile penetration exceeds 95%. The Paraguay Telecom MNO Market is expected to reach USD 699 million in 2025. Test your SMS campaigns across all three carriers for optimal delivery.

What timezone should I use for SMS sending in Paraguay?

Paraguay uses Paraguay Time (PYT) at UTC-3 permanently year-round. As of 2024, Paraguay eliminated seasonal Daylight Saving Time changes that had been observed since 1975. Send SMS between 8:00 AM – 8:00 PM local time (PYT/UTC-3). Avoid Paraguay's 14 national holidays unless sending critical notifications. Key holidays include Heroes' Day (March 1), Holy Week (Semana Santa), Workers' Day (May 1), and Independence Day.

Is two-way SMS supported in Paraguay?

No. Major SMS providers do not support two-way SMS in Paraguay. Design your messaging strategies around one-way communications only. For customer interactions requiring responses, consider alternative channels like WhatsApp (offered free with data bundles by Paraguay operators) or web-based forms.

How do I implement SMS in Paraguay using Twilio, Sinch, MessageBird, or Plivo?

All four providers support Paraguay SMS. Twilio: Use Account SID and Auth Token for authentication, format numbers as +595XXXXXXXXX in E.164 format. Sinch: Use Service Plan ID and API Token, carriers will overwrite sender IDs with local format. MessageBird: Use datacoding "auto" to handle special characters, carriers overwrite alphanumeric sender IDs. Plivo: Supports Unicode messages with Auth ID and Auth Token. All providers require proper error handling for invalid numbers, network timeouts, and carrier rejections.

Are SMS messages in Guaraní language supported in Paraguay?

Yes. SMS supports both Spanish and Guaraní, Paraguay's two official languages. According to Paraguay's 2024 National Institute of Statistics survey, 38.7% of the population speaks both languages at home, 30% communicate mainly in Guaraní, and 28.5% in Spanish. Bilingual SMS capabilities enhance reach, particularly in rural areas where Guaraní is more prevalent. Support opt-out keywords in both languages: Spanish (STOP, PARAR, BASTA) and Guaraní (AÑICHÉMA).